Mobile communication devices generally have a data input device such as a keyboard, for inputting data to the mobile device's controller, and a data output device such as a display, for communicating data from the controller to the mobile device's user. Both the data input device and data output device are typically a fixed, integral part of the mobile communication device. For example, in a conventional mobile cellular telephone, the keypad is fixed in one location on the case of the cellular telephone, as is the display.
Due to the small size of most mobile communication devices, integral data input and output devices are generally small and difficult to use. For example, the typical cellular telephone keypad and display are constrained by the size of the cellular telephone. As future cellular telephones continue to get smaller, so too must their integral keypads and displays. As the keypads become ever smaller, they become more difficult to manipulate. As the displays become ever smaller, they become more difficult to read. Thus, it would be advantageous to have a keypad and display that are not constrained by the size of the portable electronic device to which they are attached.
FIG. 1 shows a conventional cellular mobile telephone 100. Cell phone 100 has a display 110, which is typically used to show information to the user, such as dialed phone numbers. Cell phone 100 also has a keypad 120 with a plurality of keys 130. The keys 130 are generally small and difficult to manipulate, especially if cell phone 100 is small. Using the display 110 to show complex graphics or lengthy strings of text can be difficult, due to the limitations on the size of the display that are necessarily imposed by the form of the cellular telephone 100. Thus, it would be advantageous to create an input device and an output device for a portable electronic device that are not strictly limited by the size of the portable electronic device with which they are used.
Past efforts to create an input device that is not limited by the size of the portable electronic device which contains it have resulted in inventions such as the voice-activated cellular telephone. Voice-activated dialing solutions suffer from the disadvantage that voice recognition software is imperfect. Voice control systems also require considerable processing power and memory storage, both of which are typically in short supply in a portable device. Thus, it would be an advantage to create a reliable input device that allows ease of use but does not require excessive processor and memory resources from the portable electronic device.
Past efforts to create an output device that is not limited by the size of the portable electronic device that contains it have resulted in inventions such as the “virtual display.” Virtual display systems generally function in one of two ways both of which require the user to wear special glasses, either that have lenses which are used as miniature displays that are easy to read due to their proximity to the eye or that have lasers that “paint” an image onto the retina of the eye, thereby creating the illusion of a large display hanging in space in front of the user. Virtual display systems have the disadvantage that they require the user to wear, and keep track of, glasses. Thus it would be an advantage to create a display system that is not strictly limited by the size of the portable device that contains it, yet does not require that the user wear, or keep track of, extra components.